Rotary tunneling device having radially adjustable cutters



E. A. MORLAN 2,998,964

ROTARY TUNNELING DEVICE HAVING RADIALLY ADJUSTABLE CUTTERS Sept. 5, 1961 Filed March 26, 1958 a t w a INVENTOR.

BY ,fl7

ATTORNEY 2,998,964 ROTARY TUNNELING DEVICE HAVING RADIAL- LY ADJUSTABLE CUTTERS Erwin A. Morlan, Houston, Tex., assignor to Hughes Tool Company, Houston, Tex., a corporation of Delaware Filed Mar. 26, 1958, Ser. No. 124,162 4 Claims. (CL 262-7) This invention relates to machines for forming earth bores and is of particular utility in advancing, in an orderly and effective manner, large earth bores such as mine adits, vehicular tunnels, water diversion tunnels, penstock tunnels and the like.

An object of the invention is to provide an earth boring device which will expeditiously produce a smooth clean bore through rock and other earth material with comparative ease.

Another object is to provide an earth boring device which carries at its forward end a cutting structure which is capable of disintegrating earth material over the entire heading into which the bore is advancing.

It is also an object to provide an earth boring device having a cutter head with rotatable cutters thereon and means for selectively positioning the cutters to effectively cut a heading to be penetrated or to retract the cutters so that the entire device may be freely moved along the bore formed thereby.

These and other objects will be readily understood from the following description, the claims, and the accompanying drawings in which:

FIG. 1 is a perspective View of one form of the invention;

FlG. 2 is a detail of a portion of the cutter head showing one manner of driving the cutter head and for positioning the cutters radially of the head;

FIG. 3 is a perspective view of a removable cutter tooth which may be used on the rolling cutters so that cutter shells need not be discarded when the teeth have worn down.

A device embodying the invention is shown generally at 1 and comprises a forward carriage or support 2,, and a rearward carriage 3 interconnected by a frame member 4. This frame member also comprises a jack which includes rod 5 having the anchor 6 at its rearward end. A cutter head 7 is rotatably mounted upon and extends forwardly from the frame of the forward support 2.

The head 7 comprises a carrier plate 10 on shaft 11 mounted upon the frame 8. Obviously adequate bearing s for axial thrust upon the head 7 will be provided, such a bearing being shown generally at 9. The plate it? has ways 12 secured to its forward face and slidably mounted upon each such way is a cutter assembly 13. These assemblies include inner cutters 13 which cut earth material at and proximate the center of the earth bore and outer cutters 13" which cut earth material at and proximate the periphery of the bore and maintain gage of the bore.

Each cutter assembly is movable radially of the carrier plate 10 by means of a jack 14, this arrangement permitting the cutter assemblies to be desirably located upon the carrier plate 119 so that the cutters cooperatively engage and cut away the entire circular face or heading of the bore being drilled. It also enables selective retraction of the cutter assemblies toward the center of rotation of the head 7 so that there will be no interference of the head with the surrounding walls when the entire device is to be retracted from location at the heading. In this connec tion it should be noted that the innermost cutters 13 are in close contiguous relation. Hence, to provide adequate space for the inward movement of the outer cutters 13", the cutters 13' are first moved outwardly a sufficient disted States ate tance that the outer cutters 13" may be moved inwardly to a retracted position as already pointed out.

Each of the cutter assemblies 13- includes a body 15 slidably mounted upon one of the ways 12 and such body carries at its outer end a shaft 16 upon which the cutter shown generally at 17 is mounted. 'Ihese cutters have peripheral cutting elements such as teeth 18 which engage and disintegrate the earth formation 19. The cutters 17 are necessarily large in a machine capable of cutting a large bore such as a vehicular tunnel or the like. The teeth 18 may be made integral with the cutter shell as shown in FIG. 2. It is preferable, however, that the teeth be separable so that the entire cutter need not be replaced when the teeth have become worn. I have, therefore, shown in FIG. 3 a replaceable tooth 18 which may be secured to its associated cutter shell by any suitable fasteners well known in the art.

It is to be understood that the size, arrangement and number of cutting elements will be such as to give desired cutting characteristics required by various types of earth formations and that those cutters which operate at the periphery of the earth bore will have desired gage cutting structure such as the end faces of the gage or heel teeth 20 shown in FIG. 2. The cutter assembly 13 shown in this figure is shown slightly retracted from its operational position where the heel teeth 20 engage and cut the forward face or heading 21 and also maintain the gage surface or cylindrical wall 22 of the bore being formed.

The cutter head 7 may be driven by any suitable power source. However, in view of the extremely high torque necessary for producing a large bore, I prefer that each cutter assembly 13 be also used as a traction unit and to this end a prime mover such, as an electric motor 23 is mounted within a cavity in the body 15 and has its shaft 24 attached to the cutter '17. Power is supplied to the motor 23 through power cable 25. This arrangement not only eliminates the application of high torque to the head '7 but also eliminates the necessity of providing additional equipment to overcome counter torque.

The carrier plate 7 has a series of cut-away portions or pockets 26 in its periphery and a V-shaped bucket 27 is secured in each of these pockets. As the cutter head 7 rotates these buckets pick up cuttings, which accumulate at the bottom of the bore and carry these cuttings upwardly and discharge them by gravity into the hopper 2'8 whence they are discharged upon the conveyor 29 and carried rearwardly to a second hopper 3t and chute 31 for deposit in the hopper car 32.

Considerable fine dustlike material is also produced as boring progresses. To facilitate the removal of this portion of the cuttings and suppress dust a plurality of suction nozzles 33 are mounted on the support 2 and extend forward therefrom to points proximate the periphcry of cutter head '7. This material is conducted through conduit 34 and is likewise deposited in the mine car 32 so that all cuttings may be continuously removed from the area of boring operations.

The anchor 6 comprises shoes 34- mounted upon the outer ends of piston rods 35 of jacks 36 having their opposite ends pivotally attached to collar 37 on the end of rod 5 of the combination jack and framemember 4. The rearward ends of the jacks 36 are also attached to spreader jacks 33 having their inner ends pivotally attached to an extension 39 on the end of rod 5. It seems apparent that, by virtue of this anchor construction the anchor may be readily adjusted to desirably engage wall surfaces of the bore so that actuation of the main jack comprising the frame member 4 is instrumental in propelling the machine forward 'into a heading into which a bore is being advanced. v

Necessary power for actuating the various mechanisms of the device is provided by prime movers indicated generally at 40 and 41 on the mobile supports 2 and 3. Such prime movers may be self-contained or, as is well known in the arts, power may be supplied thereto as by electric cables extending to the site of operations from the mouth of the bore.

Important features of the disclosed embodiment of the invention will be emphasized by a brief explanation of the mode of operation of the device disclosed. It will be assumed that the device is located within a bore being formed and that the cutter assemblies 13 are desirably positioned upon the carrier plate that the cutters 17 thereon will disintegrate the heading at the end of the bore. The jack of frame member 4 is retracted and the jacks of the anchor 6 are so actuated that the shoes 34 of the anchor firmly engage the walls of the bore. The jack of frame member 4 is then energized to advance the cutter head 7 and at the same time the various components are energized to perform their respective functions. If desired, propulsive effort exerted by the jack of frame member 4 may be supplemented by power applied to the traction wheels on either or both of the mobile supports 2 and 3. Then, as previously explained, the cuttings formed by the cutters 17 will move downward by gravity and will be picked up by the buckets 27 and the suction nozzles 33 and conveyed to the hopper car 32 which will be replaced as necessary for continuous operation.

It is to be noted that the device is essentially a selfcontained unit. The aligned and spaced mobile sup ports provide a mobile and stable structure enhanced by the use of the main frame 4 as both a frame member and a means for propelling the device into the heading to advance the boring operation. This arrangement also provides accessibility to equipment components and other operating activities necessary for orderly progress of the boring operation. Also, the use of individual drives for some or all of the respective cutters 17 assists in minimizing the massiveness of the cutter head 7 and the drive therefor and enables easy replacement or repair of individual assemblies in event of failure.

Broadly the invention comprehends a machine of primary utility in expeditiously producing large earth bores such as tunnels used for various and well known purposes.

The invention claimed is:

1. In an earth boring machine, a cutter head including a. revoluble carrier having transverse dimensions substantially less than those of the borehole to be cut, a plurality of radially extending ways mounted on said carrier, a plurality of rolling cutters slidably mounted on said ways and having bore-forming positions to cut the full face of said bore, said cutters being disposed in at least two groups on approximately concentric circles about the axis of said bore, the outermost of said groups being thus disposed to cut the periphery of said bore and extending in said position beyond the periphery of said carrier, the sizes and dispositions of the cutters of any group relative to those of the adjacent inner group being such that the outer group may be moved radially inwardly only after the inner group is moved radially outwardly a distance sufiicient to define spaces to accommodate the members of said outer group, means for thus moving the group of cutters adjacent said outermost group outwardly and means for thus moving said outermost group of cutters inwardly within the periphery of said carrier, whereby said cutter head may be axially retracted.

2. In an earth boring machine, a cutter head including a revoluble carrier having a periphery falling substantially within the periphery of the borehole to be cut, a plurality of radially extending ways mounted on said carrier, a plurality of roller cutters slidably mounted on said ways and having bore-forming positions to cut the full face of said bore, said cutters being disposed in at least two groups on approximately concentric circles about the axis of said borehole, the outermost group being thus disposed to cut the periphery of said borehole and extending beyond the periphery of said carrier, the sizes and dispositions of any inner group relative to those of the adjacent outer group being such that members of the inner group may be moved outwardly between members of said outer group to provide previously unavailable spaces for the inward movement of the members of said outer group, and means for moving said groups of cut ters to non-bore-forming positions to define spaces for the inward movement of said outermost group of cutters within the periphery of said carrier, whereby said cutter ead may be axially retracted through said borehole with substantial clearance, said last named means including means for such inward movement of said outermost group of cutters.

3. In an earth boring machine, a cutter head including a revoluble carrier having a diameter substantially less than that of a bore to be cut, a plurality of radially extending ways mounted on said carrier, a first group of rolling cutters slidably mounted on alternate said ways and having bore-forming positions to cut formation at and proximate the center of the bore, a second group of rolling cutters slidably mounted on intermediate said ways and having bore-forming positions to cut the balance of said bore including a periphery substantially exceeding that of said carrier, said cutters being of such size and attitude in said bore-forming position as to define gaps between said first and second groups which are insutficient to permit a radial inward movement of said second group to positions within the periphery of said carriers, means for moving said first group of cutters outwardly to positions on the carrier to provide spaces for the second group of cutters, and means for thereafter moving said second group of cutters into said spaces, whereby the cutter head diameter is reduced to that of said carrier and may be retracted axially of the bore and in spaced relation with the walls thereof.

4. In a machine for forming a large bore in an earth formation, a cutter head having at least a bore-forming disposition and a retracting disposition in which there is substantial clearance with said bore, said cutter head including a revoluble carrier, a plurality of radially extending ways on said carrier, at first group of cutter assemblies slidably mounted on alternate said ways, a second group of cutter assemblies slidably mounted on intermediate said ways, and means for moving and maintaining each of said groups of cutter assemblies at various radial positions on said ways, each of said cutter assemblies including a rotatably mounted rolling cutter disposed to cut formation upon rotation of said carrier, said first group of cutter assemblies being disposed in bore-forming position to cut formation at and proximate the center of the bore and said second set of cutter assemblies being disposed in the same position to cut the balance of said bore including a periphery substantially exceeding the periphery of said carrier, the relative sizes and dispositions of said sets of cutter assemblies being such that said cutter head may be placed in retracting disposition only by first moving said first set radially outwardly and then moving said second set radially inwardly.

References Cited in the file of this patent UNITED STATES PATENTS 1,467,513 Starr et al. Sept. 11, 1923 2,711,888 Robbins et al. June 23, 1955 2,765,156 Cartlidge Oct. 2, 1956 2,766,978 Robbins Oct. 16, 1956 2,772,870 Anderson et al Dec. 4, 1956 2,775,439 McCarthy Dec. 25, 1956 2,801,094 Ball July 30, 1957 2,833,531 Joy May 6, 1958 

